AssemblyAI is an AI tool that offers a speech recognition API with state-of-the-art AI models for converting audio and live streams into text. It also enables features such as speaker detection, speech summarization, and detecting hate speech. The tool provides comprehensible documentation, tutorials, and support for developers, startups, and enterprises. AssemblyAI processes millions of audio files daily, including for Fortune 500 companies. The tool prioritizes security and requires the use of an API key to access it.